CHICAGO – Wendy French of northwest suburban Lake in the Hills used to run 10 miles a day several times a week before she caught COVID-19 in September, which left her fatigued and suffering from a variety of symptoms for months after the virus was supposedly gone.
The previously healthy 45-year-old stopped running and even began dreading typical household chores such as doing laundry, because it required standing up for so long that she grew tired.
But after French got her first dose of the Pfizer vaccine in mid-April, she described feeling healthy for the first time in more than seven months. The second dose in May brought greater improvement.
"I felt really good the next day after the first one," she said. "I had more energy than I've had in weeks."
It's a phenomenon that has surprised — and elated — medical experts: A growing number of COVID-19 "long-haulers," those with lingering long-term symptoms linked to the virus, are reporting sudden improvement after getting a COVID-19 vaccine.
Initial research has found that 30 to 40% of these patients describe some symptom relief post-vaccination, the latest medical mystery posed by the virus.
It's still unclear why some survivors don't seem to get better weeks or even months after infection. Now scientists and physicians are trying to understand why many of these patients seem to feel better after getting vaccinated, improvements that range from a mild decline in symptoms to a life-changing return to their pre-COVID-19 health.
Theories include the possibility that the vaccine might be stopping a harmful immune response in long-haulers or that the shot could be resetting their immune systems. Some clinicians and scientists have theorized that long-haulers suffer from residual amounts of virus remaining in their bodies, and vaccination might help their immune systems fight off what's left.